1. Field of the Invention
The present invention relates to a tactile sense presentation device, an electronic apparatus, and a tactile sense presentation method. More specifically, the present invention relates to a tactile sense presentation device and the like which make it possible to execute operations only with a tactile sense without looking at the hands.
2. Description of the Related Art
A display device with a touch panel to which an input can be done with a finger contributes to achieving a user-friendly interactive operability by being mounted to a system which controls display content and operations of an apparatus according to the input. Therefore, information apparatuses to which a touch panels is mounted are rapidly spread. More specifically, such apparatuses are smartphones, tablet terminals, notebook-type personal computers, and the like.
In the meantime, the surface of the display device on which the touch panel is loaded is uniformly hard, and a same tactile sense is felt when touching at any parts displayed on the screen. Thus, it is practically impossible to know which of the parts of the touch panel to touch for making an effective input or to know whether or not an effective input is made without looking at the panel. Therefore, it is difficult to operate those devices only with a tactile sense without looking at the screen of the display device.
Meanwhile, remote controllers of television set receivers, conventional-type mobile phones, keyboards of personal computers, and the like include operation keys that are independent from each other. Thus, places of the operation keys can be sensed only with a tactile sense, and it is possible to know that when pressing those operation keys through the tactile sense. Therefore, it is not so difficult to perform operations only with the tactile sense without looking at the hands by simply remembering the positions and the layout of the operations keys.
Recently, smartphones have become rapidly spread in the mobile phone terminal field, and about a half of the currently used mobile phone terminals have already been replaced with the smartphones. Accordingly, as depicted in “The Dangers of Texting while Walking”, Jun. 25, 2013, Sato Hitoshi, InfoCom, Inc., [searched on Sep. 5, 2013], Internet <URL: http://www.icr.co.jp/newsletter/global_perspective/2013/Gpre201365.html> (Non-Patent Document 1), an action executed while using smartphones, the so-called “smartphoning while walking”, has become a social problem.
It is practically impossible to operate the display device on which the touch panel is loaded only by a tactile sense without looking at the hands, so that it is necessary to operate the device while carefully looking at the screen. Therefore, to operate an electronic apparatus having such display device while walking (or while riding a bicycle, while driving/operating an automobile or the like, for example) has a high risk of causing serious injuries and accidents. Actually, there are many injuries and accidents occurred due to such actions.
Therefore, railway companies, mobile communication companies, electronic apparatus manufactures, and the like are announcing warnings for the action called “smartphoning while walking”. However, it is only a warning for bringing the attention of the users to such actions in terms of morals. A physical countermeasure for preventing such action which can be taken is only to “provide a home door on the platform of trains for preventing fall of passengers”, for example. It is currently a fact that there is no definite countermeasure taken for the smartphone itself in terms of the technical aspect for preventing “smartphoning while walking”.
Smartphones can provide comfort in the operation itself by using a touch screen when browsing Websites and video contents or when using the so-called SNS (Social Network Services). Thereby, the smartphones exhibit convenience with which a vast amount of information can be handled easily. However, there is no effective technique for making it possible to operate the smartphones only by a tactile sense without looking at the hands while maintaining the convenience. Those points described above are not only for the case of the smartphones but also for the case of tablet terminals and the like.
That is, for the information apparatuses such as smartphones, socially desired is a technique which makes it possible to present a tactile sense for the user in association with display of a touch screen for making it possible to operate only with the tactile sense without looking at the hands. Such techniques do not simply make it possible to lighten danger caused due to the action of “smartphoning while walking” but also are effective for those who are suffering from impaired vision to use such devices, for example.
As the tactile sense presenting technique for giving a tactile sense to the display device, there are following three types: a type which mechanically oscillates the display device by using a piezoelectric element, an eccentric motor, or the like; a type that uses the so-called electric oscillation phenomenon, which changes friction between a finger of the user and a tactile sense presentation device by static electricity to present a tactile sense (a sense of texture) when tracing the tactile sense presentation device with a finger; and a type which drives an axon of a skin mechanoreceptor of a finger of the user by flowing an electric current to the finger.
“Smartphones for those who are visually impaired are fantastic in the designs and functions”, Yuko Matono, Jan. 10, 2011, [searched on Sep. 5, 2013, NPO greenz, Internet <URL: http://greenz.jp/2011/01/10/braille_smartphone_voim/> (Non-Patent Document 2) describes “a smartphone for those who are visually impaired”. This smartphone does not have a normal liquid crystal display device. Instead, this smartphone has a silicone panel which presents information to the user by having protrusions appeared on the surface of the device (also has a sound information input/output module and the like). The silicone panel can present only information of low spatial resolution such as braille. Further, this technique is not for presenting information that is “associated with display on the touch screen”.
Japanese Unexamined Patent Publication 2011-248884 (Patent Document 1) describes “electric oscillation for a touch-surface” which uses the electric oscillation phenomenon. As the feature thereof, it is described as “a device which includes: a conductive surface; an insulating surface disposed on the conductive surface; and a controller which is constituted in such a manner that a signal is coupled to a user who touches the device and a tactile sense is felt thereby at least by one finger of the user sliding on the insulating surface (claims 1 of Patent Document 1), wherein “each of a plurality of electrodes is controlled by independent wirings” (paragraph 0074 in Description of Patent Document 1 and FIG. 10A).
That is, the technique depicted in Patent Document 1 intends to make it possible to present a sense of texture on the touch screen with the above-described structure.